Here's a short video that explains the holiday and it's significance to Jews.
Rosh Hashanah, the Jewish New Year, is celebrated in 2012 from sundown on Sept. 16 to nightfall on Sept. 18. The Hebrew date for Rosh Hashanah is 1 Tishrei 5773.To me, its the time I use to reflect upon the last year....the good I've done...and the bad. A time to think about how I would like to spend the coming year and what I would like to accomplish...
Though Rosh Hashanah literally means "head of the year," the holiday actually takes place on the first two days of the Hebrew month of Tishrei, which is the seventh month on the Hebrew calendar. This is because Rosh Hashanah, one of four new years in the Jewish year, is considered the new year of people, animals and legal contracts. In the Jewish oral tradition, Rosh Hashanah marks the completion of the creation of the world.
Rosh Hashanah is the beginning of the Jewish High Holy Days, or Yamim Noraim (the "Days of Awe"), and is followed 10 days later by Yom Kippur, the "day of atonement." The Mishnah refers to Rosh Hashanah as the "day of judgment," and it is believed that God opens the Book of Life on this day and begins to decide who shall live and who shall die. The days between Rosh Hashanah and Yom Kippur are viewed as an opportunity for Jews to repent (teshuvah, in Hebrew) and ensure a good fate.